The BBC’s Pat Murphy said the four may lack the mental focus required to play.
The International Cricket Council’s anti-corruption unit is preparing an urgent report, while police carry out a separate criminal investigation.
The four players being questioned are Salman Butt, Mohammad Amir, Mohammad Asif and Kamran Akmal.
Murphy added that the ICC was concerned about banning the four players based on a newspaper expose and an incomplete investigation from Scotland Yard, and therefore wanted to receive the findings from the anti-corruption unit urgently. It is expected within days.
The anti-corruption unit’s representatives are now in the UK, while the Pakistani government is sending its equivalent members to work with Scotland Yard. An ICC press conference has now been pencilled in for Thursday, our correspondent added.
ICC chief executive Haroon Lorgat told BBC Radio 5 live that the intention is to conclude the investigation before the start of the first of two Twenty20 internationals against England, in Cardiff on Sunday.
The ICC has also stated that Pakistan’s tour of England will carry on – they are due to play Somerset in a tour match from Thursday – president Sharad Pawar said it was the “desire of the ICC and the cricket boards of England and Pakistan that the game should continue”.
Lorgat added: “The reputation of the game has been tarnished and it is something we must make right. There is no question that people’s confidence will have been swayed.
“We’re busy with the Metropolitan Police and hope, before the weekend arrives, we can get to some sort of a conclusion.
“We are working hard, but it’s important to remember that an individual is innocent until proven guilty.
“I’m in touch with the investigators. It’s likely I might have to come across to London. But this is a live issue which moves with the hour, every hour.
“At the moment, it is appropriate that the game continues. We shouldn’t let everyone suffer because of a couple of individuals that might have got caught up in corrupt practices.
“The vast majority of players are not guilty of any such behaviour. They play the sport in the right spirit, and there are many fans who want to watch the game.
“We shouldn’t let a couple of individuals, a few players, bring the entire game to a standstill.”
Test captain Butt, fast bowlers Amir and Asif and wicketkeeper Akmal were questioned by police at the team’s hotel in London on Sunday following a report that some Pakistan players had been bribed to fix incidents during the fourth Test against England at Lord’s.
If any players are found to be guilty, the ICC will ensure that the appropriate punishment is handed out. (Chief executive Haroon Lorgat)
The allegations centred on three no-balls from Amir and Asif which the News of the World newspaper said had been bowled on purpose at pre-determined times to facilitate betting coups after a “middle man” accepted £150,000 in cash from an undercover reporter.
The man identified as the alleged go-between, cricket agent Mazhar Majeed, 35, has been released on police bail after being arrested on Saturday on suspicion of conspiracy to defraud bookmakers.
Investigators from the ICC’s anti-corruption and security unit are already in the UK conducting enquiries of their own as well as “assisting London’s Metropolitan Police with their criminal investigation.”
“If any players are found to be guilty, the ICC will ensure that the appropriate punishment is handed out. We will not tolerate corruption in this great game,” said Lorgat in a statement earlier.
On Monday, the Pakistan team coach left London for Taunton ahead of the match against Somerset. Pakistan are then due to continue their tour with the two Twenty20 internationals and five one-day internationals against England in September.
Test captain Butt – the one-day side is led by Shahid Afridi – boarded the coach with Amir, Asif and Akmal, plus the rest of his team-mates, despite calls from a number of quarters for the quartet to be suspended from the final part of the tour pending investigations.
There were audible, but isolated, shouts of abuse from at least one member of the public after a crowd gathered to watch the players leave London.
Somerset chief executive Richard Gould said he expected the team to receive a “warm welcome” on Thursday.
He added: “They have a net session booked in for Wednesday and if they want anything else we will be happy to provide it. This game has been looked forward to by many of our supporters and members and we think they will give the Pakistan team a warm welcome.”
Pakistan’s team manager Yawar Saeed revealed there were “sober feelings” in the dressing room, but added: “No allegations are true until they are proved.”
Australian all-rounder Shane Watson has revealed that he was been approached by an Indian bookmaker during last year’s Ashes tour of England.
“It was an Indian fan, or that’s what I thought it was, who knew a lot about me and what I did in the Indian Premier League and was only too kind with his praise about how I’ve been playing and he enjoyed the way I played,” Watson said.
“It happened a couple of times when we were at the Royal Kensington Garden in London and I just went through the right channels and (told team manager) Steve Bernard.”
However, Watson admitted to having some sympathy for 18-year-old Amir, who took six England wickets at Lord’s.
“I probably feel for him more than anyone because he’s only a young, naive and innocent young guy who is a really, really nice guy.”
Cricket agent Mazhar also owns Croydon Athletic Football Club who have released a statement saying they are “devastated and appalled to hear of the alleged match-fixing of international cricket matches by its owner Mazhar Majeed”.